Hydrangea plant named ‘H211908’

ABSTRACT

A new and distinct cultivar of  Hydrangea  plant named ‘H211908’, characterized by its upright and somewhat outwardly spreading plant habit; vigorous growth habit; strong and sturdy stems; freely flowering habit; and large inflorescences with numerous white-colored sterile flowers.

Botanical designation: Hydrangea macrophylla.

Cultivar denomination: ‘H211908’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Hydrangea plant, botanically known as Hydrangea macrophylla, commercially referred to as a mophead-type Hydrangea and hereinafter referred to by the name ‘H211908’.

The new Hydrangea plant is a product of a planned breeding program conducted by the Inventor in De Kwakel, The Netherlands and Glandorf, Germany. The objective of the breeding program was to create new freely-branching Hydrangea plants with strong and sturdy stems, large inflorescences, attractive flower color and good postproduction longevity.

The new Hydrangea plant originated from a cross-pollination made by the Inventor in April, 2007 in De Kwakel, The Netherlands, of a proprietary selection of Hydrangea macrophylla identified as code number 204168-004, not patented, as the female, or seed, parent with a proprietary selection of Hydrangea macrophylla identified as code number 204089-001, not patented, as the male, or pollen, parent. The new Hydrangea plant was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated cross-pollination in a controlled greenhouse environment in Glandorf, Germany in March, 2009.

Asexual reproduction of the new Hydrangea plant by vegetative cuttings in a controlled environment in Glandorf, Germany since June, 2009 has shown that the unique features of this new Hydrangea plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Hydrangea have not been observed under all possible environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘H211908’. These characteristics in combination distinguish ‘H211908’ as a new and distinct Hydrangea plant:

-   -   1. Upright and somewhat outwardly spreading plant habit.     -   2. Vigorous growth habit.     -   3. Strong and sturdy stems.     -   4. Freely flowering habit.     -   5. Large inflorescences with numerous white-colored sterile         flowers.

Plants of the new Hydrangea can be compared to plants of the female parent selection. Plants of the new Hydrangea differ primarily from plants of female parent selection in sterile flower color as plants of the female parent selection have light pink-colored sterile flowers.

Plants of the new Hydrangea can be compared to plants of the male parent selection. Plants of the new Hydrangea differ primarily from plants of male parent selection in inflorescence size as plants of the new Hydrangea have larger inflorescences than plants of the male parent selection.

Plants of the new Hydrangea can be compared to plants of the Hydrangea hybrida ‘Agrihydranegen’, disclosed in U.S. Plant Pat. No. 23,783. In side-by-side comparisons conducted in Glandorf, Germany, plants of the new Hydrangea differed from plants of ‘Agrihydranegen’ in the following characteristics:

-   -   1. Plants of the new Hydrangea were more vigorous than plants of         ‘Agrihydranegen’.     -   2. Plants of the new Hydrangea had larger leaves than plants of         ‘Agrihydranegen’.     -   3. Plants of the new Hydrangea had larger inflorescences than         plants of ‘Agrihydranegen’.

BRIEF DESCRIPTION OF THE PHOTOGRAPH

The accompanying colored photograph illustrates the unique appearance of the new Hydrangea plant showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photograph may differ from the color values cited in the detailed botanical description which accurately describe the colors of the new Hydrangea plant.

The photograph comprises a top perspective view of a typical flowering plant of ‘H211908’ grown in a container.

DETAILED BOTANICAL DESCRIPTION

Plants used in the aforementioned photograph and in the following description were grown during the winter in 13-cm containers in a glass-covered greenhouse in Glandorf, Germany and under cultural practices typical of commercial Hydrangea production. During the production of the plants, day and night temperatures averaged 17° C. Plants of the new Hydrangea were one year old when the photograph and description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 1995 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical description: Hydrangea macrophylla ‘H211908’. -   Parentage:     -   -   Female, or seed, parent.—Proprietary selection of Hydrangea             macrophylla identified as code number 204168-004, not             patented.         -   Male, or pollen, parent.—Proprietary selection of Hydrangea             macrophylla identified as code number 204089-001, not             patented. -   Propagation:     -   -   Type cutting.—By vegetative cuttings.         -   Time to initiate roots, summer.—About two weeks at             temperatures about 23° C.         -   Time to initiate roots, winter.—About 18 days at             temperatures about 18° C.         -   Time to produce a rooted young plant, summer.—About four             weeks at temperatures about 23° C.         -   Time to produce a rooted young plant, winter.—About five             weeks at temperatures about 18° C.         -   Root description.—Thick; whitish brown in color.         -   Rooting habit.—Freely branching; dense. -   Plant description:     -   -   Plant and growth habit.—Upright to somewhat outwardly             spreading plant habit; rounded in shape; strong and sturdy             stems; rapid growth rate and vigorous growth habit.         -   Plant height.—About 30 cm.         -   Plant diameter or area of spread.—About 35 cm to 45 cm. -   Lateral branch description:     -   -   Branching habit.—Freely branching habit with about eight             lateral branches per plant.         -   Length.—About 18 cm to 22 cm.         -   Diameter.—About 5 mm to 6 mm.         -   Internode length.—About 3.5 cm to 4.5 cm.         -   Stem texture.—Smooth, glabrous.         -   Strength.—Strong, sturdy.         -   Color.—Close to 144B overlain with close to 187A; lenticels,             close to 187A. -   Leaf description:     -   -   Arrangement.—Opposite, simple.         -   Length.—About 14 cm to 18 cm.         -   Width.—About 9 cm to 11 cm.         -   Shape.—Ovate.         -   Apex.—Acute.         -   Base.—Obtuse.         -   Margin.—Dentate.         -   Texture, upper surface.—Smooth to rugose, glabrous.         -   Texture, lower surface.—Rugose, glabrous.         -   Venation pattern.—Pinnate.         -   Color.—Developing leaves, upper surface: Close to 147A.             Developing leaves, lower surface: Close to 137C. Fully             expanded leaves, upper surface: Close to 147B; venation,             close to 145B. Fully expanded leaves, lower surface: Close             to 137C; venation, close to 145C.         -   Petiole.—Length: About 3 cm to 4 cm. Diameter: About 3 mm to             4 mm. Texture, upper and lower surfaces: Smooth, glabrous.             Color, upper and lower surfaces: Close to 145B. -   Flower description:     -   -   Flower type and habit.—Single rounded sterile and small             inconspicuous star-shaped fertile flowers arranged on             mophead-type terminal panicles; panicles globular in shape;             flowers face upright to outwardly.         -   Fragrance.—None detected.         -   Natural flowering season.—Short production time as a cooling             treatment is not required for flower development; continuous             flowering during the summer in Northern Europe.         -   Flower longevity.—Sterile flowers last about four months on             the plant, sterile flowers persistent; fertile flowers last             about one month on the plant, fertile flowers not             persistent.         -   Quantity of flowers.—Freely flowering habit; about 80             sterile flowers per panicle and about 30 fertile flowers per             panicle.         -   Panicle height.—About 10 cm.         -   Panicle diameter.—About 15 cm to 16 cm.         -   Sterile flower buds.—Length: About 2 mm. Diameter: About             2 mm. Shape: Round. Color: Close to 157D.         -   Fertile flower buds.—Length: About 4 mm. Diameter: About             3 mm. Shape: Round. Color: Close to 145C.         -   Sterile flower diameter.—About 3.5 cm to 4.5 cm.         -   Sterile flower depth (height).—About 1.5 cm.         -   Fertile flower diameter.—About 5 mm.         -   Fertile flower depth (height).—About 4 mm.         -   Petals, fertile flowers only, sterile flowers without             petals.—Quantity and arrangement: Five in a single whorl.             Length: About 2 mm to 3 mm. Width: About 2 mm. Shape: Ovate.             Apex: Acute. Base: Cuneate. Margin: Entire. Texture, upper             and lower surfaces: Smooth, glabrous. Color: When opening,             upper and lower surfaces: Close to 145D. Fully opened, upper             and lower surfaces: Close to 155B; color becoming closer to             155C with development.         -   Sepals, sterile flowers.—Quantity and arrangement: Four in a             single whorl. Length: About 2 cm to 2.5 cm. Width: About             3 cm. Shape: Roughly deltoid. Apex: Obtuse. Base: Cuneate.             Margin: Crenate. Texture, upper and lower surfaces: Smooth,             glabrous. Color: When opening, upper and lower surfaces:             Close to 144C. Fully opened, upper surface: Close to 155D;             color does not change with development. Fully opened, lower             surface: Close to 155C; color does not change with             development.         -   Sepals, fertile flowers.—Quantity and arrangement: Five in a             single whorl. Length: About 2.5 mm. Width: About 2 mm.             Shape: Ovate. Apex: Acute. Base: Obtuse. Margin: Entire.             Texture, upper and lower surfaces: Smooth, glabrous. Color:             When opening, upper and lower surfaces: Close to 145B. Fully             opened, upper surface: Close to 145B. Fully opened, lower             surface: Close to 155B.         -   Pedicels, sterile flowers.—Length: About 2 cm to 2.5 cm.             Diameter: About 2 mm to 4 mm. Strength: Strong. Texture:             Smooth, glabrous. Color: Close to 157B.         -   Pedicels, fertile flowers.—Length: About 5 mm. Diameter:             About 1.5 mm. Strength: Strong. Texture: Smooth, glabrous.             Color: Close to 157B.         -   Reproductive organs, fertile flowers only; sterile flowers             without reproductive organs.—Stamens: Quantity per flower:             Eight. Filament length: About 1 mm. Filament color: Close to             155D. Anther shape: Conical. Anther length: About 1 mm.             Anther color: Close to 155B. Pollen amount: Abundant. Pollen             color: Close to 155D. Pistils: Pistil quantity per flower:             Three. Pistil length: About 3 mm. Stigma shape: Oval. Stigma             color: Close to 155B. Style length: About 1 mm. Style color:             Close to 155B. Ovary color: Close to 155B.         -   Seeds.—Length: About 1 mm. Diameter: About 0.2 mm. Color:             Close to 200C. -   Disease & pest resistance: Under commercial production conditions,     plants of the new Hydrangea have not been observed to be resistant     to pathogens or pests common to Hydrangea plants. -   Temperature tolerance: Plants of the new Hydrangea have been shown     to be tolerant to temperatures ranging from about 3° C. to about 38°     C. 

It is claimed:
 1. A new and distinct Hydrangea plant named ‘H211908’ as illustrated and described. 